1. Field of the Invention
The present invention relates to a printing device which prints image data transmitted from an upper level device, and a method of controlling a printing device.
2. Description of the Related Art
In the related art, a printing system has been known which includes a printing device and an upper level device delivering print data to the printing device as well as instructing the printing device to perform printing. In this printing system, for example, the upper-level device generates a raster image type of print image data by using a raster image processor (RIP), on the basis of print data written in PDL (Page Description Language) that is transmitted from a host device, and transmits the generated print image data to a printing control unit of the printing device (for example, refer to Japanese Patent Application Laid-open No. 2004-287519).
Unlike the above-described printing system, a printing device is known which includes a printer controller, a printer engine, and data lines for connecting the printer controller and the printer engine (see Japanese Patent Application Laid-open No. 2002-254763). In the printing device described in Japanese Patent Application Laid-open No. 2002-254763, a control line through which various kinds of control information are transmitted and received between the printer controller and the printer engine is separated from the data lines through which printing image data is transmitted and received, thereby realizing high-speed data transmission.
Japanese Patent Application Laid-open No. 2002-254763 describes the point that image data is transmitted from the printer controller to the printer engine for each color, but there is no consideration for what kind of process the printer engine performs on image data transmitted for each color. For this reason, in the printing system having the upper level device and the printing device described in Japanese Patent Application Laid-open No. 2004-287519, when the configuration described in Japanese Patent Application Laid-open No. 2002-254763 in which the control line and the data lines are separated from each other is applied, high-speed data transmission is realized between the upper level device and the printing device. In recent years, however, with an increasing amount of print data, there is a problem in that a process in a data processing unit on the printing device side may be delayed.